Synergistic fungicidal composition comprising a compound analogous to strobilurin

ABSTRACT

A synergistic fungicidal composition comprising a compound A having the formula  
                 
 
     and a compound B which is a dicarboximide derivative such as iprodione, procymidone or vinchlozolin, and a method for controlling or preventing the development of phytopathogenic fungi employing said composition.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation of application Ser. No.09/505,874, filed Feb. 17, 2000, incorporated by reference herein in itsentirety and relied upon, which is a divisional of application Ser. No.09/051,199, filed Jul. 2, 1998, now U.S. Pat. No. 6,057,331, which isthe U.S. national phase of PCT/FR96/01532, filed Oct. 2, 1996, anddesignating the United States, and published by the International Bureauin French, not English, on Apr. 10, 1997 as WO97/12520.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The subject of the present invention is a synergistic fungicidalcomposition comprising a compound analogous to strobilurin and a processwhich makes use of the said composition and which is intended for thecurative or preventive protection of crops against fungal attacks.

[0004] 2. Background of the Prior Art

[0005] Compounds analogous to strobilurin with a fungicidal effect areknown, in particular from European Patent Publication EP 253213 or398692 or from International Publication WO 9208703, which make itpossible to prevent the growth and the development of phytopathogenicfungi capable of attacking crops.

[0006] However, it is always desirable to improve the spectrum ofactivity and the effectiveness of such compounds with a fungicidaleffect or to reinforce them by combining them with other molecules inorder to obtain a more effective product or alternatively to prevent theappearance of fungal strains which are resistant to these newfungicides.

[0007] It is also highly desirable to have available fungicidal productswhich enjoy an improved persistence of effect, likely to space out intime the number of plant-protection treatments necessary forsatisfactory control of the parasites.

[0008] It is, in any event, particularly advantageous to be able todecrease the amount of chemicals distributed in the environment, whileensuring high-performance protection of crops against fungal attacks.

[0009] It has now been found that one (or a number) of the aboveobjectives could be achieved by virtue of the fungicidal compositionaccording to the present invention.

SUMMARY OF THE INVENTION

[0010] The subject of the present invention is therefore a synergisticfungicidal composition comprising at least one compound A of formula(I):

[0011] in which:

[0012] A is the nitrogen atom or the —CH group,

[0013] B is the —OCH₂—, —CH₂O—, —C(CH₃)—O—N═CH— or —CH═N—O—CH(CH₃)—group or the group of formula (II)

[0014] R₁ is an alkyl group containing 1 to 4 carbon atoms, preferablythe methyl group,

[0015] R₂ is —OCH₃ or —NHCH₃,

[0016] X is a halogen atom, the cyano group or an alkyl or haloalkylgroup containing 1 to 4 carbon atoms, preferably the methyl ortrifluoromethyl group,

[0017] n is equal to 1 or 2, with, when n is equal to 2, the possibilityof having different X groups,

[0018] and at least one fungicidal compound B chosen from the groupcomprising dicarboximide derivatives, such as iprodione, procymidone andvinchlozolin,

[0019] the said composition comprising the components A and B in an A/Bratio by weight of between 0.02 and 5, preferably between 0.0625 and1.33,

[0020] with the proviso that when compound B is procymidone, then B informula I is the group of formula

BRIEF DESCRIPTION OF THE DRAWING

[0021] The sole FIGURE of Drawing, FIG. 1, is an isobole plot for ICIA5504, i.e. methyl(E)-2-{2-[6-(2-cyanophenoxy)pyrimidin-4-yloxy]phenyl}-3-methoxyacrylate,and iprodione in radish seedlings against Alternaria brassicae(alternaria disease).

DETAILED DESCRIPTION OF THE INVENTION, PREFERRED EMBODIMENTS AND BESTMODE

[0022] It is clearly understood that the said fungicidal composition cancontain a single compound B or more than one such compound, for example1, 2 or 3 compounds B, according to the use for which the combination isintended. Likewise, the composition may comprise more than one compoundA.

[0023] Preference is given to the fungicidal composition according tothe invention in which the compound A is methyl(E)-2-{2-[6-(2-cyanophenoxy)pyrimidin-4-yloxy]phenyl}-3-methoxyacrylate,methyl (E)-methoxyimino[α-(o-tolyloxy)-o-tolyl]acetate orN-methyl-(E)-methoxyimino[2-(2,5-dimethylphenoxymethyl)phenyl]acetamide.

[0024] Preference is further given, among the more especially preferredmeanings of the compound B defined above, to iprodione. In an entirelyunexpected way, the composition according to the invention significantlyimproves the effect of the active materials taken separately withrespect to a certain number of fungi which are particularly harmful tocrops, for example in particular grapes or the Solanaceae. Thisimprovement is reflected in particular by a decrease in the doses ofeach of the constituents, which is particularly advantageous for theuser and the environment. The fungicidal product thus exhibitssynergistic properties attested by application of the Tammes method,“Isoboles, a graphic representation of synergism in pesticides”,Netherlands Journal of Plant Pathology, 70(1964), p. 73-80 or as definedby Limpel, L. E., P. H. Schuldt and D. Lammont, 1962, Proc. NEWCC16:48-53, using the following formula, also called Colby's formula:

E=X+Y−X.Y/100

[0025] in which:

[0026] E is the expected percentage inhibition of the growth of thefungus by a mixture of the two fungicides A and B at defined doses,equal to a and b respectively;

[0027] X is the observed percentage inhibition by the fungicide A atdose a,

[0028] Y is the observed percentage inhibition by the fungicide B atdose b.

[0029] When the percentage inhibition observed for the mixture isgreater than E, there is synergism.

[0030] Preferably, when the component B is iprodione, the A/B ratio isbetween 0.05 and 5, preferably between 0.17 and 1.33, for all the cropsenvisaged.

[0031] In the particular case of lawns, the A/B ratio will generally bebetween 0.02 and 2, preferably between 0.0625 and 0.25.

[0032] The structures corresponding to the common names of thefungicidal active materials which appear in the definition of B areshown in at least one of the following 2 works:

[0033] “The Pesticide Manual”, edited by Clive Tomlin and published byThe British Crop Protection Council, 10th edition;

[0034] l'Index phytosanitaire [Plant-protection index] 1994, publishedby l'Association de Coordination Technique Agricole [AgriculturalTechnical Coordination Association], 30th edition.

[0035] As regards the derivatives analogous to strobilurin, methyl(E)-2-{2-[6-(2-cyanophenoxy)pyrimidin-4-yloxy]phenyl}-3-methoxyacrylate(or ICIA5504) is described in International Publication WO 9208703;methyl (E)-methoxyimino[α-(o-tolyloxy)-o-tolyl]acetate (or BAS490F) isdescribed in European Patent Publication EP 253213; andN-methyl-(E)-methoxyimino[2-(2,5-dimethylphenoxymethyl)phenyl]acetamide(or SSF-129) is described in European Patent Publication EP 398692.Moreover, ICIA5504 and BAS490F are listed in the abovementioned work“The Pesticide Manual”.

[0036] The fungicidal composition according to the invention comprises,as active material, at least one compound A and at least one compound Bas a mixture with solid or liquid vehicles which are acceptable inagriculture and/or surface-active agents which are also acceptable inagriculture. In particular, the inert and conventional vehicles and theconventional surface-active agents can be used. These compositions covernot only compositions which are ready to be applied to the crop to betreated by means of a suitable device, such as a spray device, but alsocommercial concentrated compositions which have to be diluted beforeapplication to the crop. The combination of at least one compound A withat least one compound B is denoted as active material.

[0037] These compositions can also contain any kind of other ingredientssuch as, for example, protective colloids, adhesives, thickening agents,thixotropic agents, penetrating agents, stabilizing agents, sequesteringagents and the like. More generally, the compounds A and B can becombined with all the solid or liquid additives corresponding to theconventional formulating techniques.

[0038] Generally, the compositions according to the invention usuallycontain from 0.05 to 95% (by weight) of active material, one or moresolid or liquid vehicles and, optionally, one or more surface-activeagents.

[0039] In the present account, the term “vehicle” denotes a natural orsynthetic, organic or inorganic material with which the active materialis combined to facilitate its application on the aerial parts of theplant. This vehicle is thus generally inert and it must be acceptable inagriculture, especially on the treated plant. The vehicle can be solid(clays, natural or synthetic silicates, silica, resins, waxes, solidfertilizers and the like) or liquid (water, alcohols, especiallybutanol, and the like).

[0040] The surface-active agent can be an emulsifying, dispersing orwetting agent of ionic or nonionic type or a mixture of suchsurface-active agents. There may be mentioned, for example, salts ofpolyacrylic acids, salts of lignosulphonic acids, salts ofphenolsulphonic or naphthalenesulphonic acids, polycondensates ofethylene oxide with fatty alcohols or with fatty acids or with fattyamines, substituted phenols, (especially alkylphenols or arylphenols),salts of esters of sulphosuccinic acids, taurine derivatives (especiallyalkyltaurates), phosphoric esters of polyoxyethylenated phenols oralcohols, esters of fatty acids and of polyols, and the derivatives ofthe above compounds containing sulphate, sulphonate and phosphatefunctional groups. The presence of at least one surface-active agent isgenerally indispensable when the active material and/or the inertvehicle is/are not soluble in water and the carrier agent forapplication is water.

[0041] The compositions for agricultural use according to the inventioncan thus contain the active material within very wide limits, rangingfrom 0.05% to 95% (by weight). Their surface-active agent content isadvantageously of between 5% and 40% by weight. Unless otherwise stated,the percentages given in this description, including the claims, are byweight.

[0042] These compositions according to the invention are themselves infairly diverse, solid or liquid forms.

[0043] There may be mentioned, as forms of solid compositions, thepowders for dusting (with an active material content which can range upto 100%) and the granules, especially those obtained by extrusion, bycompacting, by impregnation of a granulated support, or by granulationfrom a powder (the active material content in these granules beingbetween 0.5 and 80% for the latter cases), the tablets or effervescenttablets.

[0044] The fungicidal composition according to the invention can also beused in the form of powders for dusting; it is also possible to use acomposition comprising 50 g of active material and 950 g of talc; it isalso possible to use a composition comprising 20 g of active material,10 g of finely divided silica and 970 g of talc; these constituents aremixed and milled and the mixture is applied by dusting.

[0045] There may be mentioned, as forms of liquid compositions or thoseintended to constitute liquid compositions at the time of application,solutions, in particular water-soluble concentrates, emulsifiableconcentrates, emulsions, suspension concentrates, aerosols, wettablepowders (or powder to be sprayed), pastes or gels.

[0046] The emulsifiable or soluble concentrates most often comprise 10to 80% of active material, the emulsions or solutions ready forapplication containing, for their part, 0.001 to 20% of active material.

[0047] In addition to the solvent, the emulsifiable concentrate maycontain, when necessary, 2 to 20% of appropriate additives such asstabilizing agents, surface-active agents, penetrating agents, corrosioninhibitors, colorants or adhesives mentioned above.

[0048] Starting from these concentrates, it is possible to obtain, bydiluting with water, emulsions of any desired concentration which areparticularly suitable for applying to crops.

[0049] By way of example, here is the composition of a few emulsifiableconcentrates:

EC Example 1:

[0050] active material 400 g/l alkali metal dodecylbenzene  24 g/lsulphonate oxyethylated nonylphenol  16 g/l with 10 molecules ofethylene oxide cyclohexanone 200 g/l aromatic solvent qs 1 litre

[0051] According to another emulsifiable concentrate formula, thefollowing are used:

EC Example 2:

[0052] active material 250 g expoxidized vegetable oil  25 g mixture ofalkylaryl sulphonate 100 g and of ether of polyglycol and fatty alcoholsdimethylformamide  50 g xylene 575 g

[0053] The suspension concentrates, which can also be applied byspraying, are prepared so as to obtain a stable fluid product which doesnot settle out and they generally contain from 10 to 75% of activematerial, from 0.5 to 15% of surface-active agents, from 0.1 to 10% ofthixotropic agents and from 0 to 10% of suitable additives, such asantifoaming agents, corrosion inhibitors, stabilizing agents,penetrating agents and adhesives and, as vehicle, water or an organicliquid in which the active material is insoluble or nearly insoluble:certain organic solid materials or inorganic salts can be dissolved inthe vehicle to aid in preventing sedimentation or as antigels for water.

[0054] A suspension concentrate composition is given here as an example:

SC EXAMPLE 1

[0055] active material 500 g polyethoxylated tristyrylphenyl  50 gphosphate polyethoxylated alkylphenol  50 g sodium polycarboxylate  20 gethylene glycol  50 g organopolysiloxane oil (antifoaming  1 g agent)polysaccharide  1.5 g  water 316.5 g  

[0056] Wettable powders (or powder to be sprayed) are generally preparedso that they contain 20 to 95% of active material, and they generallycontain, in addition to the solid vehicle, from 0 to 30% of a wettingagent, from 3 to 20% of a dispersing agent and, when this is necessary,from 0.1 to 10% of one or more stabilizing agents and/or otheradditives, such as penetrating agents, adhesives, or anticlumpingagents, dyes, and the like.

[0057] To obtain powders to be sprayed or wettable powders, the activematerials are intimately mixed, in suitable mixers, with the additionalsubstances and the mixture is milled with mills or other suitablegrinders. Powders to be sprayed are thereby obtained with advantageouswettability and suspensibility; they can be suspended in water at anydesired concentration and these suspensions can be used veryadvantageously in particular for application to plant leaves.

[0058] Pastes can be produced in place of wettable powders. Theconditions and modes of production and use of these pastes are similarto those of wettable powders or powders to be sprayed.

[0059] Various wettable powder (or powder to be sprayed) compositionsare given here as examples:

WP EXAMPLE 1

[0060] active material 50% ethoxylated fatty alcohol (wetting 2.5% agent) ethoxylated phenylethylphenol  5% (dispersing agent) chalk (inertvehicle) 42.5%  

WP EXAMPLE 2

[0061] active material 10% C13 branched-type synthetic oxo alcohol,0.75% ethoxylated with 8 to 10 molecules of ethylene oxide (wettingagent) neutral calcium lignosulphonate 12% dispersing agent) calciumcarbonate (inert filler) qs for 100%

[0062] This wettable powder contains the same ingredients as in theabove example, in the proportions below:

WP EXAMPLE 3

[0063] active material 75% wetting agent 1.50% dispersing agent 8%calcium carbonate (inert filler) qs for 100%

WP EXAMPLE 4

[0064] active material 90%  ethoxylated fatty alcohol (wetting agent) 4%ethoxylated phenylethylphenol (dispersing agent) 6%

WP EXAMPLE 5

[0065] active material 50% mixture of anionic and nonionic surface-2.5%  active agents (wetting agent) sodium lignosulphonate (dispersingagent)  5% kaolin clay (inert vehicle) 42.5%  

[0066] Aqueous dispersions and emulsions, for example the compositionsobtained by diluting a wettable powder or an emulsifiable concentrateaccording to the invention with water, are contained within the generalscope of the present invention. Emulsions can be of the water-in-oil oroil-in-water type and they can have a thick consistency, like that of a“mayonnaise”.

[0067] The fungicidal compositions according to the invention can beformulated in the form of water-dispersible granules, which also comewithin the scope of the invention.

[0068] These dispersible granules, with a bulk density generally ofbetween approximately 0.3 and 0.6, have a particle size generally ofbetween approximately 150 and 2000 and preferably between 300 and 1500microns.

[0069] The active material content of these granules is generallybetween approximately 1% and 90%, and preferably between 25% and 90%.

[0070] The rest of the granule comprises a solid filler and, optionally,surface-active adjuvants which confer water-dispersibility properties onthe granule. These granules can be essentially of two distinct typesaccording to whether the filler chosen is soluble or insoluble in water.When the filler is water-soluble, it can be inorganic or, preferably,organic. Excellent results were obtained with urea. In the case of aninsoluble filler, the latter is preferably inorganic, such as, forexample, kaolin or bentonite. It is then advantageously accompanied bysurface-active agents (in a proportion of 2 to 20% by weight of thegranule) of which more than half comprises, for example, at least onedispersing agent, essentially anionic, such as an alkali metal oralkaline-earth metal polynaphthalenesulphonate or an alkali metal oralkaline-earth metal lignosulphonate, the remainder consisting ofnonionic or anionic wetting agents such as an alkali metal oralkaline-earth metal alkylnaphthalenesulphonate.

[0071] Moreover, although this is not indispensable, it is possible toadd other adjuvants such as antifoaming agents.

[0072] The granule according to the invention can be prepared by mixingthe necessary ingredients and then granulating according to severaltechniques known per se (granulator, fluid bed, sprayer, extrusion, andthe like). The preparation generally finishes with a crushing followedby a sieving to the particle size chosen within the limits mentionedabove. Granules obtained as above and then impregnated with acomposition containing the active material can alternatively be used.

[0073] It is preferably obtained by extrusion, by carrying out thepreparation as indicated in the examples below.

DG EXAMPLE 1 Dispersible Granules

[0074] 90% by weight of active material and 10% of urea in the form ofpearls are mixed in a mixer. The mixture is then milled in a pin mill. Apowder is obtained which is moistened with approximately 8% by weight ofwater. The moist powder is extruded in a perforated-roller extruder. Agranular material is obtained which is dried, and then crushed andsieved, so as to respectively keep only the granules with a size ofbetween 150 and 2000 microns.

DG EXAMPLE 2 Dispersible Granules

[0075] The following constituents are mixed in a mixer: active material75% wetting agent (sodium alkylnaphthalene-  2% sulphonate dispersingagent (sodium  8% polynaphthalenesulphonate) water-insoluble inertfiller (kaolin) 15%

[0076] This mixture is granulated on a fluid bed in the presence ofwater and then dried, crushed and sieved so as to obtain granules with asize of between 0.15 and 0.80 mm.

[0077] These granules can be used alone or in solution or dispersion inwater so as to obtain the required dose.

[0078] As regards the compositions which are suitable for storage andtransportation, they more advantageously contain from 0.5 to 95% (byweight) of active material.

[0079] The invention also relates to a product comprising at least onecompound A and at least one compound B as defined above for controllingphytopathogenic fungi by simultaneous, sequential or separateapplication.

[0080] Another subject of the invention is a process for controllingphytopathogenic fungi in a medium, characterized in that at least onecompound A and at least one compound B, these compounds being as definedabove, and the combination of these compounds being in an effective andnon-phytotoxic total quantity, are applied to said medium.

[0081] More precisely, the subject of the invention is a process for thecurative or preventive control of fungi which are phytopathogenic, forexample, towards crops or lawns, characterized in that an effective andnon-phytotoxic amount of a combination of at least one compound A and atleast one compound B, for example in a fungicidal composition accordingto the invention, is generally applied on the aerial parts of plants.

[0082] The fungi which are phytopathogenic towards crops which can becombated by this process are in particular those:

[0083] from the Oomycetes group:

[0084] from the Phytophthora genus, such as Phytophthora infestans(downy mildew of the Solanaceae, in particular of potatoes or tomatoes),Phytophthora citrophthora, Phytophthora capsici, Phytophthora cactorum,Phytophthora palmivora, Phytophthora cinnamoni, Phytophthora megaspermaor Phytophthora parasitica,

[0085] from the Peronosporaceae family, in particular Plasmoparaviticola (grape downy mildew), Plasmopara halstedei (sunflower downymildew), Pseudoperonospora sp (in particular downy mildew of cucurbitsand of hops), Bremia lactucae (lettuce downy mildew) or Peronosporatabacinae (tobacco downy mildew),

[0086] from the Adelomycetes group:

[0087] from the Alternaria genus, for example Alternaria solani(alternaria disease of the Solanaceae and in particular of tomatoes andpotatoes),

[0088] from the Guignardia genus, in particular Guignardia bidwellii(black rot of grapes),

[0089] from the Oidiums group, for example grape powdery mildew(Uncinula necator); powdery mildew of legumes, for example Erysiphepolygoni (powdery mildew of crucifers); Leveillula taurica, Erysiphecichoracearum, Sphaerotheca fuligena; (powdery mildew of cucurbits, ofcomposites or of tomatoes); Erysiphe communis (beet and cabbage powderymildew); Erysiphe pisi (pea or lucerne powdery mildew); Erysiphepolyphaga (bean and cucumber powdery mildew); Erysiphe umbelliferarum(powdery mildew of the Umbelliferae, in particular of carrots);Sphaerotheca humuli (hop powdery mildew); or Erysiphe graminis (powderymildew of cereals),

[0090] from the Septoria genus, for example Septoria nodorum or Septoriatritici (septoria disease of cereals);

[0091] from the Sclerotinia genus, for example Sclerotinia sclerotiniumor Sclerotinia homeocarpa (lawn sclerotinia disease),

[0092] from the Basidiomycetes group:

[0093] from the Puccinia genus, for example Puccinia recondita orstriiformis (wheat rusts),

[0094] of the Rhizoctonia spp. family.

[0095] A classification made no longer by targeted fungi but by targetcrops can be illustrated as below:

[0096] barley-helminthosporium (Helminthosporium),

[0097] rape: alternaria (Alternaria spp.), rot (Botrytis cinerea),sclerotinia disease (Sclerotinia sclerotinium),

[0098] grapes: powdery mildew (Uncinula necator), downy mildew(Plasmopara viticola), rot (Botrytis cinerea), excoriosis (Phomopsisviticola) and black rot (Guignardia bidweliii),

[0099] Solanaceae: downy mildew (Phytophthora infestans), alternariadisease (Alternaria solani) and rot (Botrytis cinerea),

[0100] legumes: downy mildews (Peronospora spp., Bremia lactucae,Pseudoperonospora spp.), or alternaria disease (Alternaria spp.),sclerotinia disease (Sclerotinia spp.), rot (Botrytis cinerea) orpowdery mildew (Erysiphe spp. or Sphaerotheca fuliginea), foot or rootrot (Rhizoctonia spp.),

[0101] rice: foot or root rot (Rhizoctonia spp.),

[0102] arboriculture: scab (Venturia inaequalis), powdery mildew(Podosphaera leucotricha), alternaria disease (Alternaria spp.), rot(Botrytis cinerea) and monilia disease (Monilia fructigena),

[0103] citrus fruits: scab (Elsinoe fawcetti), melanose (Phomopsiscitri) and diseases due to Phytophthora spp., bananas: cercosporadisease (Mycosphaerella figiensis),

[0104] lawns: rust, powdery mildew, helminthosporium disease or soildiseases (Microdochium nivale, Pythium spp., Rhizoctonia solani,Sclerotinia homeocarpa and the like).

[0105] The fungicidal composition which is the subject of the inventionis applied by means of various treatment processes, such as:

[0106] spraying a liquid comprising the said composition on the aerialparts of the crops to be treated,

[0107] dusting, the incorporation of granules or of powders into thesoil, sprinkling, injecting into trees or painting.

[0108] The spraying of a liquid on the aerial parts of the crops to betreated is the preferred treatment process.

[0109] “Effective and non-phytotoxic amount” is understood to mean anamount of composition according to the invention which is sufficient tomake possible control or destruction of the fungi present or capable ofappearing on the crops and which does not result in any notablephytotoxicity symptoms with respect to the said crops. Such an amount iscapable of varying within wide limits depending on the fungi to becombated, the type of crop, the weather conditions and the compoundsincluded in the fungicidal composition according to the invention. Thisamount can be determined by systematic tests in the field, within thescope of the person skilled in the art.

[0110] The use doses during the implementation of the process accordingto the invention will then generally be:

[0111] on barley, rape, rice, grapes, legumes, Solanaceae, bananas,arboriculture or citrus fruits:

[0112] 100 to 1000 g of compound B, e.g. iprodione +50 to 500 g/ha ofcompound A and more precisely 300 to 600 g+100 to 400 g/ha, i.e. a totaldose of compounds A and B of between 150 and 1500 g/ha, preferablybetween 400 and 1000 g/ha,

[0113] on lawns:

[0114] 1000 to 5000 g of compound B, e.g. iprodione +100 to 2000 g/ha ofcompound A and more precisely 2000 to 4000 g+250 to 1000 g/ha, i.e. atotal dose of compounds A and B of between 1100 and 7000 g/ha,preferably between 2250 and 5000 g/ha.

[0115] The following examples are given purely by way of illustration ofthe invention, which they do not limit in any way.

[0116] In the FIGURE appended to the present text, the dose of eachactive material, taken in isolation, required for control of thephytopathogenic fungus at the level indicated is compared with that ofthe 2 active materials taken as a mixture. The effective dose of eachactive material taken in isolation is shown on the axis of the abscissaeand of the ordinates and a straight line is traced cutting these 2 axesand connecting these 2 doses. When an active material taken in isolationis not effective, the straight line is parallel to the axis of thecoordinates which shows the doses of this active material. As regardsthe 2 active materials taken as a mixture, the dose of the mixture at agiven ratio is shown by a point.

EXAMPLE 1

[0117] In vivo test of the combination of ICIA5504 with iprodione withrespect to alternaria disease of radish (Alternaria brassicae) bypreventive treatment 24 hours before infection.

[0118] A suspension comprising the compounds A and B in a liquid mixturecomposed of a surface-active agent (oleate of polyoxyethylenatedderivative of sorbitan) and water is prepared.

[0119] The component B is iprodione; the A/B ratio is 0.25, 0.5, 1, 2 or4.

[0120] Radish seedlings (variety Pernot), are grown in small pots. Whenthese seedlings are 10-12 days old (cotyledon, 1st leaf stage), they aretreated by spraying with the above suspension.

[0121] Seedlings, used as controls, are treated with a similarsuspension but which does not contain active material (“formulationblank”).

[0122] After 24 hours, each seedling is infected by spraying with anaqueous suspension of spores of Alternaria brassica, which suspension isobtained from an in vitro culture of the fungus. These spores aresuspended at a concentration of 40,000 units per cm³ of inoculum.Infection is carried out by spraying the inoculum at the top surface ofthe leaves.

[0123] The infected seedlings are then incubated for six days at 18-20°C. at 90-100% relative humidity under natural light.

[0124] Reading is carried out 6 days after infection, in comparison withthe control seedlings.

[0125] The results obtained are reported in the form of points,corresponding to 80% destruction of the parasite, and are plotted on aTammes isobole diagram which contains, on the abscissa, the doses of Aexpressed in ppm (mg/l) and, on the ordinate, the doses of B, also inppm (mg/l).

[0126] The diagram of FIG. 1 is obtained. It appears that the additionof iprodione makes it possible, in an entirely unexpected way, to lowerthe dose of A necessary for the destruction of 80% of the parasite below115 ppm (mg/l), which corresponds to the dose of A alone which it isnecessary to apply to obtain the same percentage of destruction.

[0127] The arrangement of the points obtained therefore shows abilateral effect described, according to the Tammes method mentionedabove, as a “two-sided effect”. This arrangement corresponds to atype-III isobole according to the said method (page 74 of thecorresponding bibliographical reference already cited) and ischaracteristic of a synergy.

EXAMPLE 2

[0128] In vivo test of the combination of ICIA5504 with iprodione withrespect to helminthosporium disease of barley by preventive treatment 7days before infection.

[0129] The fungicides are used at the following doses:

[0130] iprodione (Rovral SC 500 g/l (B): 12.5-25-50-100-200-400-800g/ha,

[0131] ICI A5504 (SC 250 g/l)(A): 1.5-3.1-6.2-12.5-25-50-100-200 g/ha,

[0132] iprodione (B)/ICIA5504(A) 4: 6.2+1.5 to 800+200 g/ha,

[0133] iprodione/ICIA5504=2: 3.1+1.5 to 400+200 g/ha

[0134] iprodione/ICIA5504=1: 1.5+1.5 to 200+200 g/ha

[0135] iprodione/ICIA5504=0.5: 0.75+1.5 to 100+200 g/ha

[0136] The young barley plants (var. Express) which are 12 days old(first leaf developed stage) are treated with the experimentalfungicides at the doses indicated above in a slurry volume of 250 l/ha(3 repeats/dose). Seven days after the treatment, the young barleyplants are infected with a suspension of Pyrenophora teres spores(10,000 spores/ml). The young plants are incubated for 48 hours at 20°C., 100% relative humidity (RH). Next, the plants are transferred to agreenhouse at 20° C., 70-80% RH under natural light. The grading of thedisease is carried out ten days after infection by estimating the leafsurface area contaminated on the first leaf (10 young plants/pot).

[0137] By comparing with the control (non-treated-contaminated) apercentage efficacy is calculated. The synergy is then quantified byusing the Colby model. The following results are thereby obtained:

[0138] Observed Efficacy: B/A 0 g/ha 1.5 3.1 6.2 12.5 25 50 100 200 0g/ha 0 0 17.54 34.21 59.21 76.75 83.86 81.67 92.72  12.5 15.79 78.688.68 83.95 94.04  25 7.02 88.77 94.47 85.70 93.68  50 37.72 91.49 96.2392.54 90.88 100 35.09 94.65 95.53 93.33 96.23 200 47.37 95.53 97.37 95400 50.88 96.14 97.72 800 59.65 95.95

[0139] Theoretical Efficacy According to Colby: B/A 0 g/ha 1.5 3.1 6.212.5 25 50 100 200 0 g/ha 0 0 17.54 34.21 59.21 76.75 83.86 81.67 92.72 12.5 15.79 30.56 44.60 65.65 80.42  25 7.02 38.83 62.07 78.38 84.99  5037.72 74.60 85.52 89.95 88.58 100 35.09 84.91 89.52 88.10 95.27 20047.37 91.51 90.35 96.17 400 50.88 91.00 96.42 800 59.65 97.06

[0140] Synergy (% Gain): B/A 0 g/ha 1.5 3.1 6.2 12.5 25 50 100 200 0g/ha  12.5 +48 +44 +18 +14  25 +50 +32  +7 +9  50 +17 +11 +3 +2 100 +10+6 +5 +1 200 +4 +7 −1 400 +5 +1 800 −1

What is claimed is:
 1. A fungicidal composition comprising a synergisticfungicidally effective amount of a compound A which is (i) methyl(E)-methoxyimino[α-(o-tolyloxy)-o-tolyl]acetate or (ii)N-methyl-(E)-methoxyimino[2-(2,5-dimethylphenoxymethyl)phenyl]acetamide,and a compound B which is iprodione, the A/B ratio by weight beingbetween 0.02 and
 5. 2. A fungicidal composition according to claim 1,wherein compound A is methyl(E)-methoxyimino[α-(o-tolyloxy)-o-tolyl]acetate.
 3. A fungicidalcomposition according to claim 1, wherein compound A isN-methyl-(E)-methoxyimino[2-(2,5-dimethylphenoxymethyl)phenyl]acetamide.4. A fungicidal composition according to claim 1, wherein the A/B ratioby weight is between 0.0625 and 1.33.
 5. A fungicidal compositionaccording to claim 1, wherein the A/B ratio by weight is between 0.05and
 5. 6. A fungicidal composition according to claim 1, wherein the A/Bratio by weight is between 0.17 and 1.33.
 7. A fungicidal compositionaccording to claim 1, wherein the A/B ratio by weight is between 0.02and
 2. 8. A fungicidal composition according to claim 1, wherein the A/Bratio by weight is between 0.0625 and 0.25.
 9. A fungicidal compositionaccording to claim 1, further comprising at least one member selectedfrom the group consisting of an agriculturally acceptable solid orliquid vehicle and an agriculturally acceptable surface-active agent.10. A fungicidal composition according to claim 9, comprising from 0.05%to 95% by weight of compounds A and B.
 11. A process for the curative orpreventative control of phytopathogenic fungi in plants, said processcomprising applying to plants or to the locus in which they grow asynergistic fungicidally effective non-phytotoxic amount of a compound Awhich is (i) methyl (E)-methoxyimino[α-(o-tolyloxy)-o-tolyl]acetate or(ii)N-methyl-(E)-methoxyimino[2-(2,5-dimethylphenoxymethyl)phenyl]acetamide,and a compound B which is iprodione, the A/B ratio by weight beingbetween 0.02 and
 5. 12. A process according to claim 11, whereincompound A is methyl (E)-methoxyimino[α-(o-tolyloxy)-o-tolyl]acetate.13. A process according to claim 11, wherein compound A isN-methyl-(E)-methoxyimino[2-(2,5-dimethylphenoxymethyl)phenyl]acetamide.14. A process according to claim 11, wherein the A/B ratio by weight isbetween 0.0625 and 1.33.
 15. A process according to claim 11, whereinthe synergistic fungicidally effective non-phytotoxic amount of A and Bis applied to crops or lawns to control fungi which are phytopathogenictowards crops or lawns, respectively.
 16. A process according to claim15, wherein compound A ismethyl-(E)-methoxyimino[α-(o-tolyloxy)-o-tolyl]acetate.
 17. A processaccording to claim 15, wherein compound A isN-methyl-(E)-methoxyimino[2-(2,5-dimethylphenoxymethyl)phenyl]acetamide.18. A process according to claim 15, wherein the synergisticfungicidally effective non-phytotoxic amount of A and B is applied tothe aerial parts of the plants.
 19. A process according to claim 15,wherein the synergistic fungicidally effective non-phytotoxic amount ofA and B is applied to crops and wherein the A/B ratio by weight isbetween 0.05 and
 5. 20. A process according to claim 15, wherein thesynergistic fungicidally effective non-phytotoxic amount of A and B isapplied to crops and wherein the A/B ratio by weight is between 0.17 and1.33.
 21. A process according to claim 15, wherein the synergisticfungicidally effective non-phytotoxic amount of A and B is applied tocrops at a dose rate of between 150 and 1500 g/ha.
 22. A processaccording to claim 15, wherein the synergistic fungicidally effectivenon-phytotoxic amount of A and B is applied to crops at a dose rate ofbetween 400 and 1000 g/ha.
 23. A process according to claim 15, whereinthe synergistic fungicidally effective non-phytotoxic amount of A and Bis applied to lawns and wherein the A/B ratio by weight is between 0.02and
 2. 24. A process according to claim 15, wherein the synergisticfungicidally effective non-phytotoxic amount of A and B is applied tolawns and wherein the A/B ratio by weight is between 0.0625 and 0.25.25. A process according to claim 15, wherein the synergisticfungicidally effective non-phytotoxic amount of A and B is applied tolawns at a dose rate of between 1100 and 7000 g/ha.
 26. A processaccording to claim 15, wherein the synergistic fungicidally effectivenon-phytotoxic amount of A and B is applied to lawns at a dose rate ofbetween 2250 and 5000 g/ha.